Process for making three-dimensional foam-laid nonwovens

ABSTRACT

A method for making a high topography nonwoven substrate includes generating a foam including water and synthetic binder fibers; depositing the foam on a planar surface; disposing a template form on the foam opposite the planar surface to create a foam/form assembly; heating the foam/form assembly to dry the foam and bind the synthetic binder fibers; and removing the template from the substrate after heating the foam/form assembly, wherein the substrate includes a planar base layer having an X-Y surface and a backside surface opposite the X-Y surface; and a plurality of projection elements integral with and protruding in a Z-direction from the X-Y surface, wherein the projection elements are distributed in both the X- and Y-directions, and wherein the density of a projection element is the same as the density of the base layer.

BACKGROUND

A bowel movement (BM) leaking from a diaper (i.e., leak around the legarea or at the waist) causes an unpleasant mess needing clean up by acaregiver. The consumer/chooser becomes dissatisfied with the absorbentproduct of choice, which can lead to the consumer/chooser deciding toswitch to different diaper brand. As many as one in seven diaperscontaining BM result in BM leaking from the diaper. In addition, BM thatis in contact with skin can result in compromising skin health andpromoting development of diaper rash. Non-diaper skin can be healthierthan diapered skin because current diapers do a poor job of keeping BMoff of skin.

There is a lack of material/nonwoven solutions to reduce BM leakageoccurrences and keep BM off of skin. Current materials in absorbentproducts, such as spunbond, SMS, and BCW, are mostly flat, dense, and doa poor job of handling runny BM and keeping BM off of skin. There arematerials such as aperture films and textured BCW/SB composite nonwovens(e.g., TEXTOR brand nonwovens) that are used as liners. TEXTOR brandnonwovens can improve BM management properties compared to spunbondliner and is used in current products. Too many current products,however, that contain BM result in BM leakage. As a result, there is agreat opportunity to identify materials that improve absorbent productBM management performance.

SUMMARY

The materials of the present disclosure are the next step in producing adiaper that completely absorbs runny BM at the point of insult, leavingno BM spreading and no BM on the skin, to deliver zero BM leakage and acleaner skin experience. Identifying solutions to reduce BM blow outsand BM on skin is beneficial both to the wearer of the product andbecause it would result in a consumers having a more positive experiencewith such products by reducing the occurrence of diaper rash andproviding a point of differentiation from other products.

The solutions disclosed herein are nonwoven materials having highdegrees of three-dimensional (3D) topography and that have highcompression resistance while also having a high level of openness. Suchmaterials have demonstrated significantly better BM intake compared tocurrent commercial materials being using in current products. The BMFlat Plate test method has demonstrated that three-dimensional foam-laidwebs of the present disclosure reduce BM pooling to 2% wt/wt versusTEXTOR brand nonwovens at 40% wt/wt. BM pooling values are similar torewet values and represent BM on skin.

The present disclosure describes novel extreme 3D nonwoven materialsthat have superior BM management properties. Such materials can improveabsorbent products by reducing BM leakage and BM on skin. The nonwovenstructures are made possible by templating foam-laid webs, otherwiselabeled as 3D foam-laid nonwovens. The process involves dispersingbicomponent fibers in foam and templating such foam during drying &thermal bonding. This method results in extreme 3D nonwoven webs withfeatures as high as 12 mm in height and as low as 8 mm in diameter.Because of these 3D features, there is high level of Z-direction fiberorientation that results in webs having high compression resistancewhile also having a high level of openness/porosity, which are keyproperties in being able to handle runny BM. In addition, a wide varietyof 3D features, shapes, and sizes can be produced depending on templatedesign.

The present disclosure is generally directed to a method for making ahigh topography nonwoven substrate, the method including generating afoam including water and synthetic binder fibers; depositing the foam ona planar surface; disposing a template form on the foam opposite theplanar surface to create a foam/form assembly; heating the foam/formassembly to dry the foam and bind the synthetic binder fibers; andremoving the template from the substrate after heating the foam/formassembly, wherein the substrate includes a planar base layer having anX-Y surface and a backside surface opposite the X-Y surface; and aplurality of projection elements integral with and protruding in aZ-direction from the X-Y surface, wherein each projection element has aheight, a diameter or width, a cross-section, a sidewall, a proximal endwhere the projection element meets the base layer, and a distal endopposite the proximal end, wherein the projection elements aredistributed in both the X- and Y-directions, and wherein the density ofa projection element is the same as the density of the base layer.

In another aspect, the present disclosure is generally directed to amethod for making a high topography nonwoven substrate, the methodincluding generating a foam including water and synthetic binder fibers;depositing the foam on a planar surface; disposing a template form onthe foam opposite the planar surface to create a foam/form assembly;heating the foam/form assembly to dry the foam and bind the syntheticbinder fibers; and removing the template from the substrate afterheating the foam/form assembly, wherein the substrate includes syntheticbinder fibers, wherein the fibers of the substrate are entirelysynthetic binder fibers; a planar base layer having an X-Y surface and abackside surface opposite the X-Y surface; and a plurality of projectionelements integral with and protruding in a Z-direction from the X-Ysurface, wherein each projection element has a height, a diameter orwidth, a cross-section, a sidewall, a proximal end where the projectionelement meets the base layer, and a distal end opposite the proximalend, wherein the projection elements are distributed in both the X- andY-directions, wherein the shape of a cross-section of a projectionelement at the proximal end of the projection element is the same as theshape of a cross-section of a projection element at the distal end ofthe projection element, and wherein the density of a projection elementis the same as the density of the base layer.

In still another aspect, the present disclosure is generally directed toa method for making a high topography nonwoven substrate, the methodincluding generating a foam including water and synthetic binder fibers;depositing the foam on a planar surface; disposing a template form onthe foam opposite the planar surface to create a foam/form assembly;heating the foam/form assembly to dry the foam and bind the syntheticbinder fibers; and removing the template from the substrate afterheating the foam/form assembly, wherein the substrate includes syntheticbinder fibers, wherein the fibers of the substrate are entirelysynthetic binder fibers, the substrate including a planar base layerhaving an X-Y surface and a backside surface opposite the X-Y surface;and a plurality of projection elements integral with and protruding in aZ-direction from the X-Y surface, wherein each projection element has aheight, a diameter or width, a cross-section, a sidewall, a proximal endwhere the projection element meets the base layer, and a distal endopposite the proximal end, wherein the projection elements aredistributed in both the X- and Y-directions, wherein each projectionelement has a uniform density, wherein the height of a projectionelement is greater than the width or diameter of that projectionelement, and wherein the density of a projection element is the same asthe density of the base layer.

Various features and aspects of the present disclosure will be madeapparent from the following detailed description.

BRIEF DESCRIPTION OF THE FIGURES

A full and enabling disclosure of the present disclosure, including thebest mode thereof to one of ordinary skill in the art, is set forth moreparticularly in the specification, including reference to theaccompanying figures in which:

FIG. 1 is a flowchart view of an exemplary aspect of a process forproducing 3D foam-laid nonwovens in accordance with the presentdisclosure;

FIG. 2 is a perspective schematic illustration of one aspect of atemplate for use in the process of FIG. 1;

FIG. 3 photographically illustrates the results of Flow Through testingof various nonwovens including those produced by the process of FIG. 1;

FIG. 4 graphically illustrates the results of Flow Through testing ofvarious nonwovens including those produced by the process of FIG. 1;

FIG. 5 graphically illustrates the results of Compression Resistancetesting of various nonwovens including those produced by the process ofFIG. 1; and

FIG. 6 graphically illustrates the results of Air Permeability testingof various nonwovens including those produced by the process of FIG. 1.

Repeated use of reference characters in the present specification anddrawings is intended to represent the same or analogous features orelements of the present disclosure.

DETAILED DESCRIPTION

Reference now will be made to the aspects of the disclosure, one or moreexamples of which are set forth below. Each example is provided by wayof explanation of the disclosure, not as a limitation of the disclosure.In fact, it will be apparent to those skilled in the art that variousmodifications and variations can be made in the disclosure withoutdeparting from the scope or spirit of the disclosure. For instance,features illustrated or described as part of one aspect can be used onanother aspect to yield a still further aspect. Thus, it is intendedthat the present disclosure cover such modifications and variations ascome within the scope of the appended claims and their equivalents. Itis to be understood by one of ordinary skill in the art that the presentdiscussion is a description of exemplary aspects only, and is notintended as limiting the broader aspects of the present disclosure,which broader aspects are embodied in the exemplary constructions.

The present disclosure describes novel extreme 3D nonwoven materialsthat have superior BM management properties. Such materials can improveabsorbent products by reducing BM leakage and BM on skin. The nonwovenstructures are made possible by templating foam-laid webs, otherwiselabeled as 3D foam-laid webs. The process involves dispersingbicomponent fibers in foam and templating such foam during drying &thermal bonding. This method results in extreme 3D nonwoven webs withrelatively tall and narrow 3D features. Because of these 3D features,there is high level of Z-direction fiber orientation that results inwebs having high compression resistance while also having a high levelof openness/porosity, which are key properties in being able to handlerunny BM. In addition, a wide variety of 3D features, shapes, and sizescan be produced depending on template design.

Foam processes are normally used for making planar webs having a uniformthickness, such as two-dimensional shaped forms. As described herein, athree-dimensional nonwoven web is created by using a three-dimensionaltemplate to mold foam into a 3D topography. Drying and heating thetemplated foam results in a nonwoven having the topographicalcharacteristics of the template.

The process of the present disclosure obviates any further molding ofthe nonwoven web as any desired topography is created along with thecreation of the nonwoven. Prior methods of processing nonwovens requirepost-creation manipulation, cutting, embossing, or molding of anexisting nonwoven web, resulting in weakening the web along with broadvariations in web density and basis weight.

Creation of the nonwoven structures described herein requires threemajor steps: 1) Disperse binder fiber and a foaming agent in water tocreate a foam solution with a consistency some describe as shavingcream-like. 2) Template the fiber/foam blend. 3) Dry and heat the blendto remove water and to activate the binder fibers, thus setting the 3Dstructure in the nonwoven. These webs are referred to herein as 3Dfoam-laid nonwovens.

In the first step, binder fiber and a foaming agent are dispersed inwater to create a foam solution with a consistency some describe asshaving cream-like. This step involves dispersing a blend of fiberscapable of forming fiber-fiber bonds (e.g., bicomponent fibers/binderfibers) in a foam solution. This is done by mixing fibers, water, andfoaming agent such as sodium dodecyl sulfate (SDS) surfactantsimultaneously to create a foam and to uniformly suspend the fibers inthe foam. This foaming process creates a stable foam containing afibrous network that is uniformly dispersed through the foam solution.The foam has high viscosity, preventing fibers from floating, sinking,and/or agglomerating.

Many types of fibers can be included in the fiber blend, but the blendmust include binder fibers in a quantity sufficient to ensure the final3D foam-laid nonwoven has integrity and can maintain its 3D structuralfeatures. In one example, the fiber blend is 100% wt/wt binder fibershaving a polyethylene sheath and a polypropylene core. The binder fibersare typically synthetic, thermoplastic bonder fibers. In other aspects,the binder fibers can be bi- and/or multi-component binder fibers. Inother aspects, the fiber blend can include cellulosic fibers.

In another aspect of the present disclosure, nanovoided technology hasproduced lightweight, uncrimped bicomponent staple fiber with a fiberdensity reduction of 20-33%. Use of such lightweight fibers in the fiberblend can increase the fiber count for the same basis weight, thusincreasing the web compression resistance. In various aspects, thelow-density fiber can have density as low as 0.5 grams/cubic centimeteror even lower. In an example, the low density-voided fibers used canhave a density of 0.62 g/cc, which equates to the polyolefin-based fiberhaving a 33% reduction in overall density with a 47% void volume in thecore. Foam forming is a preferred method of forming a nonwoven webcontaining low-density fibers and enables lofty webs using voided fibersthat do not require stuffer box crimped fibers. For example, carded websrequire fibers to be stuffer box crimped to form a web. Stuff boxcrimping is a high pressure process that results in internal fiber voidstructure destruction and thus cannot generate a carded web includinglow-density voided fibers. Because of the high viscosity foam,low-density fibers are able to be properly laid into a web using thefoam as carrier, thus enabling the ability to form webs includinglow-density fibers.

Although some level of binder fibers is required, the fiber blend doesnot need to contain solely binder fibers; other types of fibers can beincorporated into the fiber blend. The selection of fibers can includeall types of synthetic fibers to a wide range of natural fibers. Thefibers can have a wide range of cut length/fiber length, such as from3-30 mm. A wide range of fiber diameters can also be used. A widevariety of foaming agents and amounts can be used such as anionic andnon-ionic in amounts ranging from 0.1-5 wt %. Typically, SDS has beenused at about 0.17 wt % to water. Foam density can range from 100-400g/L. Foam stability half-life can range from 2-30 min. Fiber consistency(fiber concentration) can range from 0.5-5% wt/wt.

In the second step, the fiber/foam blend is poured onto or applied inany suitable manner to a foraminous belt or other suitable surface. Thebelt optionally includes a frame-type mold to limit the spread of thefiber/foam blend on the belt. A template is then placed on top of thefiber/foam blend, typically within the mold if present. The templateprovides a negative pattern to the desired pattern of the 3D foam-laidnonwoven. In one illustrative example, if a convex surface is desiredfor the nonwoven, then the template will have a concave surface pattern.Upon placement of the template, the fiber/foam blend conforms to thetopography of the template, in essence creating bumps of foam where thetemplate has dimples, dimples where the template has bumps, and flatspaces where the template is flat. In this manner, the template createsa 3D topography in the foam.

Typically the template contains cavities into which the fiber/foam blendcan flow and fill. Cavity sizes range from 8 mm in diameter or largerand cavity depths can be as large as the thickness of the applied foam,as large as 50 mm or more. In one example, the template cavities are 12mm deep. The cavities can have any suitable shape, including round,rectangular, square, triangular, mushroom-shaped, symbols, toroidal, ormore complex combinations of shapes, and the template cavities can haveany combination of shapes, sizes, and depths, or the template cavitiescan be of one uniform shape, size, and depth, as long as the fiber/foamblend can flow and fill the cavities in the template.

The template material should be selected to withstand bondingtemperatures. Examples of template materials include silicon, metal,polyurethane, polytetrafluoroethylene, and any other suitable material.The template material should also be selected such that fibers do notadhere to template, thereby allowing easy removal of the web from thetemplate, or the template from the web, after thermal activation of thebinder fiber. In other words, the binder fibers should preferably adhereto other binder fibers rather than the template material. In general,increased fiber-to-fiber bonding overcomes fiber-to-template bondingproblems. The template should also be open enough to allow proper airflow and heat transfer to enable drying and heat activation of thebinder fiber.

In the third step, the templated fiber/foam blend is placed in an ovenor other suitable heating device to dry and thermally bond the binderfibers. It is important that the template is present during thedrying/bonding stage to ensure the 3D structure will be present in thefinal web. Temperatures and time in the oven should be long enough toremove a sufficient amount of water and to sufficiently activate thebinding fiber. The time and temperature can be set by one skilled in theart based on the ingredients in the fiber/foam blend, the volume andsurface area of the fiber/foam blend, the specifications of the ovenused, the initial conditions of the templated fiber/foam blend, and anyother relevant conditions.

The process described herein produces unique webs. Different hightopography 3D nonwovens can be produced by selecting different templates(e.g., templates with different cavity sizes, shapes, depths, spacing,etc.). The 3D foam-laid nonwovens produced by the process describedherein typically have a base layer defining an X-Y plane, where the baselayer has an X-Y surface and a backside surface opposite the X-Ysurface.

The 3D foam-laid nonwovens also include vertical (Z-direction) featuressuch as projection elements protruding in the Z-direction from andintegral with the base layer. This is often called a “peak and valley”type 3D structure. Each projection element has a height, a diameter orwidth, a cross-section, a sidewall, a proximal end where the projectionelement meets the base layer, and a distal end opposite the proximalend. The projection elements are typically distributed in both the X-and Y-directions. The projection elements can be uniformly distributedin both the X- and Y-directions, or the pattern of projection elementscan be varied in either or both directions.

Depending on the template design, may different vertical feature shapesand sizes can be created. For example, a horizontal cross-section of aprojection element can have any suitable shape, including round,rectangular, square, triangular, mushroom-shaped, symbols, toroidal, ormore complex combinations of shapes. The height of the vertical featurescan range from 1 mm to 50 mm or greater, 1 mm to 30 mm, 5 mm to 50 mm, 5mm to 30 mm, 30 mm to 50 mm, or any other suitable range of heights. Thewidth or diameter of a vertical feature, depending on the shape of itscross-section, can be 8 mm or greater. The heights of the projectionelements are preferably greater than the width or diameter of theprojection elements. In various aspects, the ratio of the height of aprojection element to the width or diameter of that projection elementis greater than 0.5.

Because of the manner in which the 3D foam-laid nonwoven is produced,the density of a projection element is generally the same as or similarto the density of the base layer. In various aspects, the shape of across-section of a projection element at the proximal end of theprojection element is the same as the shape of a cross-section of aprojection element at the distal end of the projection element.Alternatively, the shape of a cross-section of a projection element atthe proximal end of the projection element can be different from theshape of a cross-section of a projection element at the distal end ofthe projection element. The density of a projection element at theproximal end of the projection element can be the same as or differentfrom the density of a projection element at the distal end of theprojection element. The basis weight of a projection element at theproximal end of the projection element can be the same as or differentfrom the density a projection element at the distal end of theprojection element. In other aspects, the size of a cross-section of aprojection element at the proximal end of the projection element can bethe same as or different from the size of a cross-section of aprojection element at the distal end of the projection element.

Each projection element can have an internally-uniform density. In otherwords, each projection element generally has a homogeneous densitylargely free of hollow or densified portions. The projection elementscan have a density between 0.001 and 0.02 g/cc. The 3D foam-laidnonwovens demonstrate a basis weight range from 15 gsm to 120 gsm,although lower or higher basis weights can be produced using the processdescribed herein.

Because of the manner in which the 3D foam-laid nonwoven is produced,the projection elements and particularly the sidewalls of the projectionelements have fibers aligned in the Z-direction. In some aspects, thesidewalls have greater than 50 percent of fibers oriented in theZ-direction. Because of high degree of fiber z-direction orientation,the 3D foam-laid nonwovens described herein demonstrate very highcompression resistance while also being very open and having a highlevel of porosity. For the purpose of comparison, “flat” bonded cardedweb (BCW) surge provides compression resistance of about 25 cc/g at 0.6kPa pressure. The 3D foam-laid nonwovens of the present disclosureprovide compression resistance from about 35 up to 65 cc/g at 0.6 kPapressure. In addition, these high level of compression resistance isachievable with very open web structures. Again for the purpose ofcomparison, 100 gsm MGL9 surge, a standard BCW-type surge material, hasan air permeability value of about 440 cfm, while the 3D foam-laidnonwovens measure between 1000 and 2500 cfm.

Bench testing of 3D foam-laid nonwovens has demonstrated superior BMmanagement properties. For example, a test method for BM flow measuresthe amount of BM simulant that transfers from a BM-simulant-insultednonwoven to blotter paper. A liner made from TEXTOR brand nonwoventypically results in about 40% of BM simulant remaining on the surfaceof the liner as shown using the blotter paper (i.e., the amountremaining is also called % pooled). The 3D foam-laid nonwovens of thepresent disclosure have demonstrated about half the amount of % pooling(i.e., 20%) compared to the TEXTOR brand nonwoven at about half thebasis weight of TEXTOR brand nonwoven (55 gsm TEXTOR brand nonwovencompared to 30 gsm 3D foam-laid nonwoven). At higher basis weights, suchas a 60 gsm 3D foam-laid nonwoven, demonstrated less than 2% BM simulant% pooled. The % pooled indicator can be consider analogous to “what ison skin” or rewet.

Examples Procedures Air Permeability Test

Air Permeability was measured in cubic feet of air per minute passingthrough a 38 square cm area (circle with 7 cm diameter) using a TextestFX3300 air permeability tester manufactured by Textest Ltd., Zurich,Switzerland. All tests were conducted in a laboratory with a temperatureof 23±2° C. and 50±5% relative humidity. Specifically, a nonwoven sheetis allowed to dry out and condition for at least 12 hours in the 23±2°C. and 50±5% relative humidity laboratory before testing. The nonwovensheet is clamped in the 7 cm diameter sheet test opening and the testeris set to a pressure drop of 125 Pa. Placing folds or crimps above thefabric test opening is to be avoided if at all possible. The unit isturned on by applying clamping pressure to the sample. The air flowunder the 125 Pa pressure drop is recorded after 15 seconds of airflowto achieve a steady state value.

The Air Permeability Test measures the rate of airflow through a knowndry specimen area. The air permeability of each sample was measuredusing a Textest FX3300 air permeability tester available from SchmidCorporation, having offices in Spartanburg, S.C.

A specimen from each test sample was cut and placed so the specimenextended beyond the clamping area of the air permeability tester. Thetest specimens were obtained from areas of the sample that were free offolds, crimp lines, perforations, wrinkles, and/or any distortions thatmake them abnormal from the rest of the test material.

The tests were conducted in a standard laboratory atmosphere of 23±1° C.(73.4±1.8° F.) and 50±2% relative humidity. The instrument was turned onand allowed to warm up for at least 5 minutes before testing anyspecimens. The instrument was calibrated based on the manufacturer'sguidelines before the test material was analyzed. The pressure sensorsof the instrument were reset to zero by pressing the NULL RESET buttonon the instrument. Before testing, and if necessary between samples orspecimens, the dust filter screen was cleaned, following themanufacturer's instructions. The following specifications were selectedfor data collection: (a) Unit of measure: cubic feet per minute (cfm);(b) test pressure: 125 Pascal (water column 0.5 inch or 12.7 mm); and(c) test head: 38 square centimeters (cm²). Because test resultsobtained with different size test heads are not always comparable,samples to be compared should be tested with the same size test head.

The NULL RESET button was pressed prior to every series of tests, orwhen the red light on the instrument was displayed. The test head wasopen (no specimen in place) and the vacuum pump was at a complete stopbefore the NULL RESET button was pressed.

Each specimen was placed over the lower test head of the instrument. Thetest was started by manually pressing down on the clamping lever untilthe vacuum pump automatically started. The Range Indicator light on theinstrument was stabilized in the green or yellow area using the RANGEknob. After the digital display was stabilized, the air permeability ofthe specimen was displayed, and the value was recorded. The testprocedure was repeated for 10 specimens of each sample, and the averagevalue for each sample was recorded as the air permeability.

Compression Test Method

From the target nonwoven, a 38 mm by 25 mm test sample was cut. Theupper and lower platens made of stainless steel were attached to atensile tester (Model: Alliance RT/1 manufactured by MTS SystemCorporation, a business having a location in Eden Prairie, Minn.,U.S.A.). The top platen had a diameter of 57 mm while the lower platenhad a diameter of 89 mm. The upper platen was connected to a 100 N loadcell while the lower platen was attached to the base of the tensiletester. TestWorks Version 4 software program provided by MTS was used tocontrol the movement of the upper platen and record the load and thedistance between the two platens. The upper platen was activated toslowly move downward and touch the lower platen until the compressionload reached around 5000 g. At this point, the distance between the twoplatens was zero. The upper platen was then set to move upward (awayfrom the lower platen) until the distance between the two platensreaches 15 mm. The crosshead reading shown on TestWorks Version 4software program was set to zero. A test sample was placed on the centerof the lower platen with the projections facing toward the upper platen.The upper platen was activated to descend toward the lower platen andcompress the test sample at a speed of 25 mm/min. The distance that theupper platen travels was indicated by the crosshead reading. This was aloading process. When 345 grams of force (about 3.5 kPa) was reached,the upper platen stopped moving downward and returned at a speed of 25mm/min to its initial position where the distance between the twoplatens was 15 mm. This was an unloading process. The compression loadand the corresponding distance between the two platens during theloading and unloading were recorded on a computer using TestWorksVersion 4 software program provided by MTS. The compression load wasconverted to the compression stress by dividing the compression force bythe area of the test sample. The distance between the two platens at agiven compression stress represented the thickness under that particularcompression stress. A total of three test samples were tested for eachtest sample code to get representative loading and unloading curves foreach test sample code.

Flow Through Test Method

The Flow Through Test was performed using Simulant A, which was appliedto the targeted nonwoven. The BM simulant was applied using a BM gun andthe absorption test conducted using the BM Plate Test Method. Thetargeted nonwoven was the material described herein. The four corners ofthe BM plate were then adjusted to match nonwoven thickness and checkedto make sure the plate was level. The nonwoven was placed between thelower and upper plates and insulted with BM simulant. The nonwoven wasleft in the test apparatus for 2 minutes after insult, and then placedon a vacuum box to measure the amount of BM simulant pooling on thenonwoven. Four paper towels were placed on top of the nonwoven and thenonwoven was flipped with the paper towels down on top of the vacuum boxand covered with a silicone sheet to seal the vacuum. The vacuum box wasturned on pulling a pressure of 5 inches of water for 1 minute. Inaddition to the BM simulant picked-up by paper towels on the vacuum box,the excess BM simulant left on the BM plate was removed using anadditional paper towel. The BM simulant amount picked up by the papertowels from the vacuum box along with the excess BM simulant left on theplate was recorded as the total pooled BM simulant.

Three (N=3) samples were tested for each of the examples. The amounts ofBM simulant in each layer in the 3 samples were then averaged to get BMsimulant pooled on the nonwoven.

Materials Fibers

Voided bicomponent fibers with a diameter of 33 microns, a denier of 5.5dpf, and a density of 0.705 g/cc. Non-voided bicomponent fibers with adiameter of 33 microns, a denier of 7.1 dpf, and a density of 0.913g/cc. Note that the density of the voided bicomponent fibers was 23percent less than the density of the non-voided bicomponent fibers. Thefiber density was measured using sink/float after web thermal bonding at133° C. The fibers were cut to a length of 18 mm, then heat set at 118°C. for a final length of 15 mm. The codes tested are listed in Table 1.

TABLE 1 Codes Tested Code Target Basis Number Fiber Weight, in gsm 1Voided 30 2 Voided 60 3 Voided 120 4 Non-Voided 30 5 Non-Voided 60 6Non-Voided 120

The three-dimensional foam-laid handsheets tested herein were producedby combining 300 grams of deionized water, 5 grams of 10% SDS, andfibers. The combination was mixed to foam and poured into an 8 inch by 8inch by 2 inch frame. This was then templated with a template havingsquare holes of 1 cm, an openness of 40%, and a thickness of 12 mm, witha nylon spunbond backing. The assembly was dried and thermal bonded at133° C. for 1 to 1.5 hours. This was then wet dipped in 0.2% wt/wt ofSILWET brand DA63 surfactant in water and dried in ambient conditions.

Fecal Material Simulant

The following is a description of the fecal material simulant A used inthe examples described herein.

Ingredients:

DANNON brand All Natural Low-fat Yogurt (1.5% milkfat grade A), Vanillawith other natural flavor, in 32 oz container.

MCCORMICK brand Ground Turmeric

GREAT VALUE brand 100% liquid egg whites

KNOX brand Original Gelatin—unflavored and in powder form

DAWN brand Ultra Concentrated original scent dishwashing liquid

Distilled Water

Note: All fecal material simulant ingredients can be purchased atgrocery stores such as WAL-MART brand stores or through on-lineretailers. Some of the fecal material simulant ingredients areperishable food items and should be incorporated into the fecal materialsimulant at least two weeks prior to their expiration date.

Mixing Equipment:

Laboratory Scale with an accuracy to 0.01 gram

500 mL beaker

Small lab spatula

Stop watch

IKA-WERKE brand Eurostar Power Control-Vise with R 1312 Turbine stirreravailable from IKA Works, Inc., Wilmington, N.C., USA.

Mixing Procedure:

1. A 4-part mixture is created at room temperature by adding, in thefollowing order, the following fecal material simulant ingredients(which are at room temperature) to the beaker at a temperature between21° C. and 25° C.: 57% yogurt, 3% turmeric, 39.6% egg white, and 0.4%gelatin. For example, for a total mixture weight of 200.0 g, the mixturewill have 114.0 g of the yogurt, 6.0 g of the turmeric, 79.2 g of theegg whites, and 0.8 g of the gelatin.

2. The 4-part mixture should be stirred to homogeneity using theIKA-WERKE brand Eurostar stirrer set to a speed of 50 RPM. Homogeneitywill be reached in approximately 5 minutes (as measured using the stopwatch). The beaker position can be adjusted during stirring so theentire mixture is stirred uniformly. If any of the mixture materialclings to the inside wall of the beaker, the small spatula is used toscrape the mixture material off the inside wall and place it into thecenter part of the beaker.

3. A 1.3% solution of DAWN brand dishwashing liquid is made by adding1.3 grams of DAWN brand Ultra Concentrated dishwashing liquid into 98.7grams of distilled water. The IKA-WERKE brand Eurostar and the R 1312Turbine stirrer is used to mix the solution for 5 minutes at a speed of50 RPM.

4. An amount of 2.0 grams of the 1.3% DAWN brand dishwashing liquidsolution is added to 200 grams of the 4-part mixture obtained from Step2 for a total combined weight of 202 grams of fecal material simulant.The 2.0 grams of the 1.3% DAWN brand dishwashing liquid solution isstirred into the homogenous 4-part mixture carefully and only tohomogeneity (approximately 2 minutes) at a speed of 50 RPM, using theIKA-WERKE brand Eurostar stirrer. Final viscosity of the final fecalmaterial simulant should be 390±40 cP (centipoise) when measured at ashear rate of 10 s⁻¹ and a temperature of 37° C.

5. The fecal material simulant is allowed to equilibrate for about 24hours in a refrigerator at a temperature of 7° C. It can be stored in alidded and airtight container and refrigerated for up to 5 days ataround 7° C. Before use, the fecal material simulant should be broughtto equilibrium with room temperature. It should be noted that multiplebatches of fecal material simulant of similar viscosity can be combined.For example, five batches of fecal material simulant of similarviscosity and each 200 grams can be combined into one common containerfor a total volume of 1000 cc. It will take approximately 1 hour for1000 cc of fecal material simulant to equilibrate with room temperature.

Results

Results of the Flow Through Tests are illustrated in FIGS. 3 and 4. 3Dfoam-laid nonwovens using voided and non-voided binder fibers behavedsimilarly in the tests. When compared to the results of the TEXTOR brandnonwoven test, the 3D foam-laid nonwoven test demonstrated approximatelyhalf the % pooling at nearly half the basis weight. Higher basis weight3D foam-laid nonwovens demonstrated approximately less than 2% %pooling. In addition, there is a higher level of BM simulant passingthrough the 3D foam-laid nonwoven, even at a basis weight of 60 gsm.

Results of compression and air permeability tests are illustrated inFIGS. 5 and 6. The 3D foam-laid nonwovens of the present disclosureexhibit high compression resistance and high air permeability. In thispeak and valley model, the combination of open valleys and compressionresistant peaks is an arrangement resulting in low % pooling values.

The solutions disclosed herein are nonwoven materials having highdegrees of 3D topography, high compression resistance, and a high levelof openness. Such materials demonstrate significantly better BM intakecompared to current commercial materials used in current products. TheBM Flat Plate test method has demonstrated that the 3D foam-laidnonwovens of the present disclosure can reduce BM pooling to 2% wt/wt,as compared to TEXTOR brand nonwovens at 40% wt/wt. BM pooling valuescan be considered analogous to rewet values and represent BM on skin.

In a first particular aspect, a method for making a high topographynonwoven substrate includes generating a foam including water andsynthetic binder fibers; depositing the foam on a planar surface;disposing a template form on the foam opposite the planar surface tocreate a foam/form assembly; heating the foam/form assembly to dry thefoam and bind the synthetic binder fibers; and removing the templatefrom the substrate after heating the foam/form assembly, wherein thesubstrate includes a planar base layer having an X-Y surface and abackside surface opposite the X-Y surface; and a plurality of projectionelements integral with and protruding in a Z-direction from the X-Ysurface, wherein each projection element has a height, a diameter orwidth, a cross-section, a sidewall, a proximal end where the projectionelement meets the base layer, and a distal end opposite the proximalend, wherein the projection elements are distributed in both the X- andY-directions, and wherein the density of a projection element is thesame as the density of the base layer.

A second particular aspect includes the first particular aspect, whereinthe binder fibers are bi- and/or multi-component binder fibers.

A third particular aspect includes the first and/or second aspect,wherein the shape of a cross-section of a projection element at theproximal end of the projection element is the same as the shape of across-section of a projection element at the distal end of theprojection element.

A fourth particular aspect includes one or more of aspects 1-3, whereinthe shape of a cross-section of a projection element at the proximal endof the projection element is different from the shape of a cross-sectionof a projection element at the distal end of the projection element.

A fifth particular aspect includes one or more of aspects 1-4, whereinthe shape of a cross-section of a projection element is circular, oval,rectangular, or square.

A sixth particular aspect includes one or more of aspects 1-5, whereinthe density of a projection element at the proximal end of theprojection element is the same as the density of a projection element atthe distal end of the projection element.

A seventh particular aspect includes one or more of aspects 1-6, whereinthe basis weight of a projection element at the proximal end of theprojection element is the same as the density a projection element atthe distal end of the projection element.

An eighth particular aspect includes one or more of aspects 1-7, whereinthe size of a cross-section of a projection element at the proximal endof the projection element is different from the size of a cross-sectionof a projection element at the distal end of the projection element.

A ninth particular aspect includes one or more of aspects 1-8, whereineach projection element has a uniform density.

A tenth particular aspect includes one or more of aspects 1-9, whereinthe height of a projection element is greater than the width or diameterof that projection element.

An eleventh particular aspect includes one or more of aspects 1-10,wherein the substrate has a compression resistance that provides 20cubic centimeters or more of void volume per gram of substrate at 0.6kPa pressure.

A twelfth particular aspect includes one or more of aspects 1-11,wherein the ratio of the height of a projection element to the width ordiameter of a projection element is greater than 0.5.

A thirteenth particular aspect includes one or more of aspects 1-12,wherein the height of a projection element is greater than 3 mm.

A fourteenth particular aspect includes one or more of aspects 1-13,wherein the sidewalls have greater than 50 percent of fibers oriented inthe Z-direction.

A fifteenth particular aspect includes one or more of aspects 1-14,wherein the synthetic binder fibers have an average length greater than3 mm.

A sixteenth particular aspect includes one or more of aspects 1-15,wherein the projection elements have a density between 0.001 and 0.02g/cc.

A seventeenth particular aspect includes one or more of aspects 1-16,wherein the projection elements are uniformly distributed in both the X-and Y-directions.

In an eighteenth particular aspect, a method for making a hightopography nonwoven substrate includes generating a foam including waterand synthetic binder fibers; depositing the foam on a planar surface;disposing a template form on the foam opposite the planar surface tocreate a foam/form assembly; heating the foam/form assembly to dry thefoam and bind the synthetic binder fibers; and removing the templatefrom the substrate after heating the foam/form assembly, wherein thesubstrate includes synthetic binder fibers, wherein the fibers of thesubstrate are entirely synthetic binder fibers; a planar base layerhaving an X-Y surface and a backside surface opposite the X-Y surface;and a plurality of projection elements integral with and protruding in aZ-direction from the X-Y surface, wherein each projection element has aheight, a diameter or width, a cross-section, a sidewall, a proximal endwhere the projection element meets the base layer, and a distal endopposite the proximal end, wherein the projection elements aredistributed in both the X- and Y-directions, wherein the shape of across-section of a projection element at the proximal end of theprojection element is the same as the shape of a cross-section of aprojection element at the distal end of the projection element, andwherein the density of a projection element is the same as the densityof the base layer.

In a nineteenth particular aspect, a method for making a high topographynonwoven substrate includes generating a foam including water andsynthetic binder fibers; depositing the foam on a planar surface;disposing a template form on the foam opposite the planar surface tocreate a foam/form assembly; heating the foam/form assembly to dry thefoam and bind the synthetic binder fibers; and removing the templatefrom the substrate after heating the foam/form assembly, wherein thesubstrate includes synthetic binder fibers, wherein the fibers of thesubstrate are entirely synthetic binder fibers, the substrate includinga planar base layer having an X-Y surface and a backside surfaceopposite the X-Y surface; and a plurality of projection elementsintegral with and protruding in a Z-direction from the X-Y surface,wherein each projection element has a height, a diameter or width, across-section, a sidewall, a proximal end where the projection elementmeets the base layer, and a distal end opposite the proximal end,wherein the projection elements are distributed in both the X- andY-directions, wherein each projection element has a uniform density,wherein the height of a projection element is greater than the width ordiameter of that projection element, and wherein the density of aprojection element is the same as the density of the base layer.

A twentieth particular aspect includes the nineteenth particular aspect,wherein the shape of a cross-section of a projection element at theproximal end of the projection element is the same as the shape of across-section of a projection element at the distal end of theprojection element.

These and other modifications and variations to the present disclosuremay be practiced by those of ordinary skill in the art, withoutdeparting from the spirit and scope of the present disclosure, which ismore particularly set forth in the appended claims. In addition, itshould be understood that aspects of the various aspects may beinterchanged both in whole and in part. Furthermore, those of ordinaryskill in the art will appreciate that the foregoing description is byway of example only, and is not intended to limit the disclosure sofurther described in such appended claims.

What is claimed:
 1. A method for making a high topography nonwovensubstrate, the method comprising: generating a foam including water andsynthetic binder fibers; depositing the foam on a planar surface;disposing a template form on the foam opposite the planar surface tocreate a foam/form assembly; heating the foam/form assembly to dry thefoam and bind the synthetic binder fibers; and removing the templatefrom the substrate after heating the foam/form assembly, wherein thesubstrate includes a planar base layer having an X-Y surface and abackside surface opposite the X-Y surface; and a plurality of projectionelements integral with and protruding in a Z-direction from the X-Ysurface, wherein each projection element has a height, a diameter orwidth, a cross-section, a sidewall, a proximal end where the projectionelement meets the base layer, and a distal end opposite the proximalend, wherein the projection elements are distributed in both the X- andY-directions, and wherein the density of a projection element is thesame as the density of the base layer.
 2. The method of claim 1, whereinthe binder fibers are bi- and/or multi-component binder fibers.
 3. Themethod of claim 1, wherein the shape of a cross-section of a projectionelement at the proximal end of the projection element is the same as theshape of a cross-section of a projection element at the distal end ofthe projection element.
 4. The method of claim 1, wherein the shape of across-section of a projection element at the proximal end of theprojection element is different from the shape of a cross-section of aprojection element at the distal end of the projection element.
 5. Themethod of claim 1, wherein the shape of a cross-section of a projectionelement is circular, oval, rectangular, or square.
 6. The method ofclaim 1, wherein the density of a projection element at the proximal endof the projection element is the same as the density of a projectionelement at the distal end of the projection element.
 7. The method ofclaim 1, wherein the basis weight of a projection element at theproximal end of the projection element is the same as the density aprojection element at the distal end of the projection element.
 8. Themethod of claim 1, wherein the size of a cross-section of a projectionelement at the proximal end of the projection element is different fromthe size of a cross-section of a projection element at the distal end ofthe projection element.
 9. The method of claim 1, wherein eachprojection element has a uniform density.
 10. The method of claim 1,wherein the height of a projection element is greater than the width ordiameter of that projection element.
 11. The method of claim 1, whereinthe substrate has a compression resistance that provides 20 cubiccentimeters or more of void volume per gram of substrate at 0.6 kPapressure.
 12. The method of claim 1, wherein the ratio of the height ofa projection element to the width or diameter of a projection element isgreater than 0.5.
 13. The method of claim 1, wherein the height of aprojection element is greater than 3 mm.
 14. The method of claim 1,wherein the sidewalls have greater than 50 percent of fibers oriented inthe Z-direction.
 15. The method of claim 1, wherein the synthetic binderfibers have an average length greater than 3 mm.
 16. The method of claim1, wherein the projection elements have a density between 0.001 and 0.02g/cc.
 17. The method of claim 1, wherein the projection elements areuniformly distributed in both the X- and Y-directions.
 18. A method formaking a high topography nonwoven substrate, the method comprising:generating a foam including water and synthetic binder fibers;depositing the foam on a planar surface; disposing a template form onthe foam opposite the planar surface to create a foam/form assembly;heating the foam/form assembly to dry the foam and bind the syntheticbinder fibers; and removing the template from the substrate afterheating the foam/form assembly, wherein the substrate includes syntheticbinder fibers, wherein the fibers of the substrate are entirelysynthetic binder fibers; a planar base layer having an X-Y surface and abackside surface opposite the X-Y surface; and a plurality of projectionelements integral with and protruding in a Z-direction from the X-Ysurface, wherein each projection element has a height, a diameter orwidth, a cross-section, a sidewall, a proximal end where the projectionelement meets the base layer, and a distal end opposite the proximalend, wherein the projection elements are distributed in both the X- andY-directions, wherein the shape of a cross-section of a projectionelement at the proximal end of the projection element is the same as theshape of a cross-section of a projection element at the distal end ofthe projection element, and wherein the density of a projection elementis the same as the density of the base layer.
 19. A method for making ahigh topography nonwoven substrate, the method comprising: generating afoam including water and synthetic binder fibers; depositing the foam ona planar surface; disposing a template form on the foam opposite theplanar surface to create a foam/form assembly; heating the foam/formassembly to dry the foam and bind the synthetic binder fibers; andremoving the template from the substrate after heating the foam/formassembly, wherein the substrate includes synthetic binder fibers,wherein the fibers of the substrate are entirely synthetic binderfibers, the substrate including a planar base layer having an X-Ysurface and a backside surface opposite the X-Y surface; and a pluralityof projection elements integral with and protruding in a Z-directionfrom the X-Y surface, wherein each projection element has a height, adiameter or width, a cross-section, a sidewall, a proximal end where theprojection element meets the base layer, and a distal end opposite theproximal end, wherein the projection elements are distributed in boththe X- and Y-directions, wherein each projection element has a uniformdensity, wherein the height of a projection element is greater than thewidth or diameter of that projection element, and wherein the density ofa projection element is the same as the density of the base layer. 20.The method of claim 1, wherein the shape of a cross-section of aprojection element at the proximal end of the projection element is thesame as the shape of a cross-section of a projection element at thedistal end of the projection element.